CN106771947A - A kind of detection circuit and its detection method for IGBT surge currents - Google Patents
A kind of detection circuit and its detection method for IGBT surge currents Download PDFInfo
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- CN106771947A CN106771947A CN201611060556.5A CN201611060556A CN106771947A CN 106771947 A CN106771947 A CN 106771947A CN 201611060556 A CN201611060556 A CN 201611060556A CN 106771947 A CN106771947 A CN 106771947A
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- igbt
- detection circuit
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/26—Testing of individual semiconductor devices
- G01R31/2607—Circuits therefor
- G01R31/2608—Circuits therefor for testing bipolar transistors
Abstract
The invention provides a kind of detection circuit and its detection method for IGBT surge currents, its detection circuit includes：Charge circuit and discharge loop；Charge circuit includes：The high-voltage charging unit of series connection, charge switch and storage capacitor；Discharge loop includes：The auxiliary IGBT of series connection, load inductance and discharge switch；Wherein, charge switch is connected with discharge switch, and high-voltage charging unit is connected with storage capacitor and auxiliary IGBT respectively.The auxiliary IGBT set in the technical scheme that the present invention is provided and SECO switching realize the detection of detection and disjunction surge current ability to IGBT tolerances, and feasible analogy method is provided to verify whether IGBT meets dc circuit breaker this special operation condition.
Description
Technical field
It is in particular to a kind of for the detection circuit of IGBT surge currents and its inspection the present invention relates to field of power electronics
Survey method.
Background technology
The characteristics of Technology of HVDC based Voltage Source Converter has highly controllable, flexible and efficient, in large-scale distributed regenerative resource
Access, the aspect such as ocean archipelago powers, send out in marine wind electric field cluster, new city power network builds, with significant advantage, be
The important directions of following power network development.
In Technology of HVDC based Voltage Source Converter, dc circuit breaker is the nucleus equipment for ensureing direct current network safe operation, and it can
The reliability of network system, and crimp type IGBT device are directly determined by property as the core devices in dc circuit breaker, its
Performance And Reliability directly determines the breaking capacity of dc circuit breaker and the reliability of work.IGBT devices in dc circuit breaker
The application operating mode of part is different from the application operating mode of IGBT in other equipment such as soft straight converter valve.Dc circuit breaker concern is primarily with
In a short time, tolerance is more than the surge current of rated current several times and the ability of this surge current of disjunction for IGBT device.
Tested IGBT needs to be carried out in the case of no-voltage open-minded, opens rear electric current near normal and rises to specified electricity
Stream, subsequent electric current is turned off after rising to several times rated current with a slow slope, and electric current is rapid when IGBT device is turned off
Decline, while measured device both end voltage slowly rises to specified high voltage.
In tested IGBT device waveform as shown in Figure 1, T1 is additional device service time；T2 is that measured device is open-minded
Current rise time, the slow rising peak of electric current is measured device several times rated current；T3 is current-off time, device shut-off
While voltage begin to ramp up, voltage rising time is much larger than current-off time, and voltage rises to the continuous ruuning situation of device
Under maximum allowable shut-off voltage.
In order to detect IGBT device whether meet dc circuit breaker needed for ability, it is necessary to design a kind of measure loop, but
This special measure loop there is no clear and definite circuit topological structure at present, the measure loop and equipment of conventional IGBT device without
Method pointedly checks IGBT device to the tolerance and turn-off capacity of this big surge current, therefore also cannot just check this
Whether IGBT device is applied to dc circuit breaker.
Accordingly, it is desirable to provide the need for a kind of detection circuit is to meet prior art.
The content of the invention
In order to overcome the above-mentioned deficiencies of the prior art, the present invention provide the application introduce it is a kind of for IGBT surge currents
Detection circuit and its method.
Detection circuit, including：Charge circuit and discharge loop；
Charge circuit includes：The high-voltage charging unit of series connection, charge switch and storage capacitor；Discharge loop includes：Series connection
Auxiliary IGBT, load inductance and discharge switch；
Wherein, charge switch is connected with discharge switch, high-voltage charging unit be provided with respectively with storage capacitor and with auxiliary
IGBT connected interface.
IGBT is in parallel with the series arm that Absorption Capacitance is constituted with arrester branch road, diode for auxiliary.Absorption Capacitance two ends
It is parallel with resistance.Load inductance is in parallel with fly-wheel diode.
The both positive and negative polarity of high-voltage charging unit is connected with one end of charge switch and with one end of storage capacitor respectively；Energy storage electricity
The other end of appearance is connected with the other end of charge switch.
One end of discharge switch is connected with charge switch, the other end respectively with the positive pole of load inductance and fly-wheel diode
Negative pole is connected；The anode of fly-wheel diode and the negative pole of load inductance colelctor electrode, the positive pole of diode respectively with auxiliary IGBT
And arrester connection；The negative pole of diode is connected with the positive pole of Absorption Capacitance and the other end of resistance respectively.
Aid in the grid connection control signal of IGBT.Aid in the two ends tested IGBT in parallel of IGBT.
The detection method of above-mentioned detection circuit, comprises the following steps：
A. when detecting that circuit is off, the grid of IGBT is aided in connect negative electricity in tested IGBT and discharge loop
It is flat；
B. after high-voltage charging unit power taking, charge switch is closed, storage capacitor charges；
C. after the voltage of storage capacitor reaches busbar voltage, charge switch is disconnected, closes discharge switch.
Step C includes：After aiding in the grid of IGBT to connect positive level conducting, the emitter current of IGBT is aided in slowly to rise,
After reaching predetermined time t2, the grid of tested IGBT connects positive level while shut-off auxiliary IGBT；
When the emitter current of tested IGBT rapidly increases to t3 moment, the grid voltage of IGBT is aided in be changed into low level
When, when the emitter current of tested IGBT is raised slowly to t4 moment, the tested IGBT of shut-off；
When the emitter current of tested IGBT drops to zero, detection is completed.
With immediate prior art ratio, the present invention provide technical scheme have the advantages that：
1st, by the present invention in that with the auxiliary IGBT in discharge loop, realizing that the no-voltage of tested IGBT is open-minded, and shut-off
IGBT two ends are tested afterwards produces high voltage.
2nd, the present invention can obtain the slow of tested IGBT both end voltages in tested IGBT two ends parallel connection RCD buffer loops
Rise and the rapid Detection results for declining of electric current.
3rd, the SECO by aiding in IGBT and tested IGBT of the invention, realizes the rapid change of current of electric current to measured device
Afterwards, the detection demand that can rise by setting slope is met.
4th, method of the present invention using auxiliary IGBT and SECO switching is set, realizes the tested IGBT tolerances energy of detection
The ability of power and disjunction surge current, for checking IGBT whether meet dc circuit breaker this special operation condition provide it is a kind of practical
Feasible analogy method.
Brief description of the drawings
Fig. 1 is the voltage current waveform schematic diagram of tested IGBT device；
Fig. 2 is detection circuit topological structure schematic diagram of the invention；
Fig. 3 is the control signal and its voltage current waveform schematic diagram of detection circuit of the invention.
Specific embodiment
Technical scheme is described in further details with reference to Figure of description.
As shown in Fig. 2 present invention detection circuit structure part has charge circuit and discharge loop, wherein charge circuit
Including：High-voltage charging unit U, storage capacitor C and charge switch S1, discharge loop include：It is discharge switch S2, load inductance L, continuous
Stream diode D, auxiliary IGBT, absorption circuit (diode D1, Absorption Capacitance C1, buffer resistance R, arrester MOV).
Detect that circuit is with the connected mode of tested IGBT：The a ends of high-voltage charging unit U positive poles connection charge switch S1,
The b ends of charge switch S1 connect a ends of discharge switch S2 and the positive plate of storage capacitor, the b ends connection load of discharge switch S2
The positive pole of inductance L and the negative electrode of sustained diode, the tested IGBT's of anode and load inductance L negative poles connection of sustained diode
The a ends of colelctor electrode, the colelctor electrode, diode D1 anodes and arrester MOV of auxiliary IGBT, diode D1 negative electrodes connection Absorption Capacitance
The positive plate of C1 and a ends of resistance R, be tested the emitter stage of IGBT, the auxiliary emitter stage of IGBT, the negative plate of Absorption Capacitance C1,
The b ends of resistance R and the b ends of arrester MOV connect the negative pole of storage capacitor C and high-voltage charging unit U, are tested IGBT and auxiliary
IGBT grids connect control signal.
The detection circuit control sequential is：Before on-test, switch S1 and S2 disconnects, and is tested IGBT and auxiliary IGBT grid
Pole adds negative level, device shut-off.From after 380V AC network power takings, closure charge switch S1 gives energy storage electricity to high-voltage charging unit U
Hold C to charge, after electric capacity two ends reach busbar voltage, disconnect charge switch S1, close discharge switch S2, preparation starts experiment.
As shown in figure 3, at the t1 moment, positive level, control auxiliary IGBT conductings are added to auxiliary IGBT grids；At the t2 moment,
Add positive level, the tested IGBT conductings of control to tested IGBT grids；At the t3 moment, negative level is added to auxiliary IGBT grids, controlled
Auxiliary IGBT shut-offs；At the t4 moment, negative level, the tested IGBT shut-offs of control are added to tested IGBT grids；In tested IGBT shut-offs
Afterwards, treat that device current drops to zero, after voltage rises to stationary value, detection is completed.
High-tension electricity charhing unit charges to electric capacity, by capacitances to supply power during experiment；Because electric current is larger, electric current disjunction moment can produce
The larger voltage overshoot of life, needs strict control loop stray inductance, and suppress voltage mistake by absorption circuit in parallel and arrester
Protection device is rushed, and arrester also plays the effect of clamp voltage.Simultaneously according to actual waveform demand, need to add in major loop
Enter an inductance L and turn the device on rear electric current and slowly rise.
The continuous auxiliary IGBT in parallel of measured device, aids in IGBT to first turn on, and electric current is closed after rising to certain value, together
When control gate signal open tested IGBT, the loop current of tested IGBT is climbed to certain value, slowly rising to
Turned off after several times load current value.Device is opened moment by the change of current and reach a current value IC1, then electric current start slowly
Rise, after reaching Preset Time, shut-off device current declines rapidly, while voltage starts slow rising is similar to soft switching.
Finally it should be noted that：The above embodiments are merely illustrative of the technical solutions of the present invention rather than its limitations, institute
The those of ordinary skill in category field specific embodiment of the invention can still be modified with reference to above-described embodiment or
Equivalent, these are applying for this pending hair without departing from any modification of spirit and scope of the invention or equivalent
Within bright claims.
Claims (10)
1. a kind of detection circuit for IGBT surge currents, it is characterised in that including：Charge circuit and discharge loop；
The charge circuit includes：The high-voltage charging unit of series connection, charge switch and storage capacitor；
The discharge loop includes：The auxiliary IGBT of series connection, load inductance and discharge switch；
Wherein, the charge switch is connected with the discharge switch, and the high-voltage charging unit is provided with electric with the energy storage respectively
The interface for holding and being connected with the auxiliary IGBT.
2. detection circuit according to claim 1, it is characterised in that the auxiliary IGBT and arrester branch road, diode
It is in parallel with the series arm that Absorption Capacitance is constituted.
3. detection circuit according to claim 2, it is characterised in that the Absorption Capacitance two ends are parallel with resistance.
4. detection circuit according to claim 3, it is characterised in that the both positive and negative polarity of the high-voltage charging unit respectively with institute
State one end of charge switch and be connected with one end of the storage capacitor；The other end of the storage capacitor and the charge switch
The other end connection.
5. detection circuit according to claim 4, it is characterised in that the load inductance is in parallel with fly-wheel diode.
6. detection circuit according to claim 5, it is characterised in that one end of the discharge switch and the charge switch
Connection, the other end is connected with the positive pole of the load inductance and the negative pole of the fly-wheel diode respectively；
The negative pole of the anode of the fly-wheel diode and the load inductance respectively with colelctor electrode, described two of the auxiliary IGBT
The positive pole of pole pipe and the arrester are connected；
The negative pole of the diode is connected with the positive pole of the Absorption Capacitance and the other end of the resistance respectively.
7. detection circuit according to claim 6, it is characterised in that the grid connection control signal of the auxiliary IGBT.
8. detection circuit according to claim 7, it is characterised in that the two ends of the auxiliary IGBT tested IGBT in parallel.
9. it is a kind of it is as claimed in claim 1 detection circuit detection method, it is characterised in that comprise the following steps：
A. when the detection circuit is off, the grid of tested IGBT and auxiliary IGBT connects negative level；
B. after high-voltage charging unit power taking, charge switch is closed, storage capacitor charges；
C. after the voltage of the storage capacitor reaches busbar voltage, the charge switch is disconnected, closes discharge switch.
10. detection method according to claim 9, it is characterised in that the step C includes：
After the grid of the auxiliary IGBT connects positive level conducting, the emitter current of the auxiliary IGBT slowly rises, and reaches pre-
If after moment t2, the grid of the tested IGBT connects positive level while turning off the auxiliary IGBT；
When the emitter current of the tested IGBT rapidly increases to t3 moment, the grid voltage of the auxiliary IGBT is changed into low
During level, when the emitter current of the tested IGBT is raised slowly to t4 moment, the tested IGBT is turned off；
When the emitter current of the tested IGBT drops to zero, detection is completed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611060556.5A CN106771947B (en) | 2016-11-25 | 2016-11-25 | Detection circuit and detection method for IGBT surge current |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611060556.5A CN106771947B (en) | 2016-11-25 | 2016-11-25 | Detection circuit and detection method for IGBT surge current |
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| CN106771947A true CN106771947A (en) | 2017-05-31 |
| CN106771947B CN106771947B (en) | 2020-10-13 |
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Cited By (9)
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|---|---|---|---|---|
| CN107765160A (en) * | 2017-08-29 | 2018-03-06 | 全球能源互联网研究院有限公司 | The test circuit and method of testing of a kind of IGBT device |
| CN107807319A (en) * | 2017-09-22 | 2018-03-16 | 全球能源互联网研究院有限公司 | A kind of insulated gate bipolar transistor IGBT test circuit and method |
| CN109239570A (en) * | 2018-10-31 | 2019-01-18 | 中国振华集团永光电子有限公司（国营第八七三厂） | A kind of diode forward current surge experimental circuit |
| CN109425811A (en) * | 2017-08-21 | 2019-03-05 | 上海新微技术研发中心有限公司 | IGBT detection circuit and detection method |
| CN110412443A (en) * | 2019-08-19 | 2019-11-05 | 西安易恩电气科技有限公司 | A kind of MOSFET avalanche test circuit |
| CN110988736A (en) * | 2019-12-10 | 2020-04-10 | 天津瑞能电气有限公司 | Short circuit test tool |
| CN111142044A (en) * | 2020-02-05 | 2020-05-12 | 东南大学 | Direct current line fault secondary detection device with short-circuit fault energy absorption capacity |
| CN112363037A (en) * | 2019-07-25 | 2021-02-12 | 华润微电子（重庆）有限公司 | Limit performance verification circuit, system and method for field effect transistor |
| CN113824093A (en) * | 2021-08-23 | 2021-12-21 | 中国船舶重工集团公司第七一一研究所 | Solid-state circuit breaker and buffer absorption circuit used for same |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109425811A (en) * | 2017-08-21 | 2019-03-05 | 上海新微技术研发中心有限公司 | IGBT detection circuit and detection method |
| CN107765160A (en) * | 2017-08-29 | 2018-03-06 | 全球能源互联网研究院有限公司 | The test circuit and method of testing of a kind of IGBT device |
| CN107807319A (en) * | 2017-09-22 | 2018-03-16 | 全球能源互联网研究院有限公司 | A kind of insulated gate bipolar transistor IGBT test circuit and method |
| CN107807319B (en) * | 2017-09-22 | 2020-03-10 | 全球能源互联网研究院有限公司 | Insulated gate bipolar transistor IGBT test circuit and method |
| CN109239570A (en) * | 2018-10-31 | 2019-01-18 | 中国振华集团永光电子有限公司（国营第八七三厂） | A kind of diode forward current surge experimental circuit |
| CN112363037A (en) * | 2019-07-25 | 2021-02-12 | 华润微电子（重庆）有限公司 | Limit performance verification circuit, system and method for field effect transistor |
| CN112363037B (en) * | 2019-07-25 | 2024-03-01 | 华润微电子（重庆）有限公司 | Field effect transistor limit performance verification circuit, system and method |
| CN110412443A (en) * | 2019-08-19 | 2019-11-05 | 西安易恩电气科技有限公司 | A kind of MOSFET avalanche test circuit |
| CN110988736A (en) * | 2019-12-10 | 2020-04-10 | 天津瑞能电气有限公司 | Short circuit test tool |
| CN111142044A (en) * | 2020-02-05 | 2020-05-12 | 东南大学 | Direct current line fault secondary detection device with short-circuit fault energy absorption capacity |
| CN111142044B (en) * | 2020-02-05 | 2022-03-18 | 东南大学 | Direct current line fault secondary detection device with short-circuit fault energy absorption capacity |
| CN113824093A (en) * | 2021-08-23 | 2021-12-21 | 中国船舶重工集团公司第七一一研究所 | Solid-state circuit breaker and buffer absorption circuit used for same |
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